In our co-pending application for U.S. patent Ser. No. 12/831,587, “Solar Cell Assembly with Diffraction Gratings”, filed Jul. 7, 2010, we disclosed the use of a diffraction grating in combination with dye sensitized and organic solar cells wherein the diffraction grating is structured to couple a first order diffraction component of normal incident light into an absorbing layer. In general, the combination enhances the efficiency of dye sensitized and/or organic absorbent-type solar cells.
The diffraction gratings as disclosed in our co-pending application are “single groove” diffraction gratings; i.e., gratings having a single periodicity and a regular pattern of groove width and spacing between the grooves of the diffraction grating.